Nox2 underpins microvascular inflammation and vascular contributions to cognitive decline

Chronic microvascular inflammation and oxidative stress are inter-related mechanisms underpinning white matter disease and vascular cognitive impairment (VCI). A proposed mediator is nicotinamide adenine dinucleotide phosphate (NADPH) oxidase 2 (Nox2), a major source of reactive oxygen species (ROS) in the brain. To assess the role of Nox2 in VCI, we studied a tractable model with white matter pathology and cognitive impairment induced by bilateral carotid artery stenosis (BCAS). Mice with genetic deletion of Nox2 (Nox2 KO) were compared to wild-type (WT) following BCAS. Sustained BCAS over 12 weeks in WT mice induced Nox2 expression, indices of microvascular inflammation and oxidative damage, along with white matter pathology culminating in a marked cognitive impairment, which were all protected by Nox2 genetic deletion. Neurovascular coupling was impaired in WT mice post-BCAS and restored in Nox2 KO mice. Increased vascular expression of chemoattractant mediators, cell-adhesion molecules and endothelial activation factors in WT mice post-BCAS were ameliorated by Nox2 deficiency. The clinical relevance was confirmed by increased vascular Nox2 and indices of microvascular inflammation in human post-mortem subjects with cerebral vascular disease. Our results support Nox2 activity as a critical determinant of VCI, whose targeting may be of therapeutic benefit in cerebral vascular disease.     

福建口岸三蚊种COI基因序列分析

〔目的〕分析福建口岸白纹伊蚊、中华按蚊和骚扰阿蚊细胞色素C氧化酶亚基I(COI)基因序列,为建立蚊种分子鉴定方法奠定基础。〔方法〕扩增并测定在福建口岸采集的白纹伊蚊、中华按蚊和骚扰阿蚊COI基因序列,与GenBank中相应序列进行对比分析。〔结果〕三蚊种COI基因扩增片段长度约500bp,A+T含量为65.61%~68.73%。核苷酸同源性分析结果表明,同一蚊种COI基因同源性为98.1%~100%,三蚊种间基因同源性为84.4%~87.7%;COI部分基因系统进化关系显示,三蚊种COI分子鉴定与形态学鉴定结果一致,阿蚊属与伊蚊属聚类为库蚊亚科,按蚊亚科位于系统进化树另一分支。〔结论〕COI基因核苷酸序列分析可应用于福建国境口岸三蚊种的区分,弥补形态特征信息量不足等传统分类鉴定方法的缺点,为建立外来或新发现蚊种分子鉴定方法奠定基础。     

LOX与VEGF蛋白在人喉鳞癌中的表达及其相关性研究

目的检测赖氨酰氧化酶（LOX）、血管内皮生长因子（VEGF）蛋白在人喉鳞癌中的表达,探讨其对喉鳞癌转移及预后的影响及意义。方法采用免疫组织化学方法检测14例有淋巴结转移的喉鳞癌及24例未见淋巴结转移的原位癌组织中LOX及VEGF的表达情况,并分析其表达的相关性。结果①LOX、VEGF在喉鳞癌组织中表达显著高于癌旁正常组织（P均〈0．05）。②VEGF在淋巴结转移组与无转移组表达阳性率分别为100％和71％,具有显著性差异（P〈0．05）;LOX在淋巴结转移组与无转移组表达无显著性差异（P〉0．05）。③LOX、VEGF的表达与患者的年龄、性别、临床分型及临床分期等临床病理因素无关。④LOX与VEGF在人喉鳞癌组织中表达呈正相关。结论LOX与VEGF存在正相关性,可作为喉癌治疗的一个新靶点。VEGF的高表达可能是造成LOX表达变化的重要影响因素之一。     

Histone deacetylase inhibitors inhibit cervical cancer growth through Parkin acetylation-mediated mitophagy

Parkin, an E3 ubiquitin ligase, plays a role in maintaining mitochondrial homeostasis through targeting damaged mitochondria for mitophagy. Accumulating evidence suggests that the acetylation modification of the key mitophagy machinery influences mitophagy level, but the underlying mechanism is poorly understood. Here, our study demonstrated that inhibition of histone deacetylase (HDAC) by treatment of HDACis activates mitophagy through mediating Parkin acetylation, leading to inhibition of cervical cancer cell proliferation. Bioinformatics analysis shows that Parkin expression is inversely correlated with HDAC2 expression in human cervical cancer, indicating the low acetylation level of Parkin. Using mass spectrometry, Parkin is identified to interact with two upstream molecules, acetylase acetyl-CoA acetyltransferase 1 (ACAT1) and deacetylase HDAC2. Under treatment of suberoylanilide hydroxamic acid (SAHA), Parkin is acetylated at lysine residues 129, 220 and 349, located in different domains of Parkin protein. In in vitro experiments, combined mutation of Parkin largely attenuate the interaction of Parkin with PTEN induced putative kinase 1 (PINK1) and the function of Parkin in mitophagy induction and tumor suppression. In tumor xenografts, the expression of mutant Parkin impairs the tumor suppressive effect of Parkin and decreases the anticancer activity of SAHA. Our results reveal an acetylation-dependent regulatory mechanism governing Parkin in mitophagy and cervical carcinogenesis, which offers a new mitophagy modulation strategy for cancer therapy.     

中国上海汉族人群NAD(P)H氧化酶p22phox亚基C242T基因多态性与脑卒中相关性

目的:研究NAD(P)H氧化酶p22phox亚基C242T基因多态性与脑卒中的相关性?方法:收集118例脑出血患者?125例脑梗死患者和147例正常对照组,研究对象均来自上海地区汉族人群,3组在年龄?性别构成比?体质指数(BMI)等基线指标均没有明显差异,分别进行血糖?血脂等各项指标的测定,用聚合酶链反应?限制性片段长度多态性分析(PCR－RFLP)和基因测序方法比较其在不同人群中的基因突变频率?结果:脑出血组?脑梗死组CT + TT基因型(9.3%?9.6%)和T等位基因(4.7%?5.2%),均明显高于对照组(2.0%和1.0%,P < 0.05),脑梗死组中发现1例TT基因型,出血组与正常对照组均未发现TT基因型,与基因测序结果一致?采用二分类Logistic回归分析p22phox亚基C242T基因多态性与脑出血的相关性(β = 1.712,OR = 5.537,95%CI:1.120~27.381,P = 0.036),与脑梗死的相关性(β = 1.432,OR = 4.187,95%CI:0.934~18.774,P = 0.061),表明C242T基因多态性可能是脑出血?脑梗死的危险因素?结论:NAD(P)H氧化酶p22phox亚基C242T多态性与脑出血?脑梗死均有一定的相关性,可能是脑卒中的一个危险因素?但与高血压和饮酒等传统危险因素相比,C242T多态性对脑梗死的影响并不显著?     

鬼箭羽三种提取物对氧自由基作用的影响

目的观察鬼箭羽(Euonymus Alatus,EA)主要提取物对氧自由基的影响.方法从鬼箭羽中分离出总黄酮(Total Flavonolds of Euonymus Alatus,TFEA)、总甾体(Total Steroids of Euonymus Alatus,TSEA)和总多糖(Total Polysaccharide of Euonymus Alatus,TPEA),利用黄嘌呤/黄嘌呤氧化酶(Xanthine/Xanthine oxidase,Xan/XO)和多形核白细胞(Polymorphonuclear leaukocytes.PMN)呼吸爆发介导鲁米诺化学发光(Chemluminesence,CL)体系H2O2诱导大鼠肝匀浆脂质过氧化体系进行实验,观察3种成分对氧自由基作用的影响.结果 TFEA和TSEA有良好的清除氧自由基作用,其中TFEA效果最好,TSEA次之.结论鬼箭羽提取物具有抗氧化作用,其主要成分是TFEA、TSEA和TPEA.     

RNAi下调LOX表达对人肺癌细胞乏氧转移的影响及其分子机制

目的观察RNA干扰（RNAi）下调赖氨酸氧化酶（lysyl oxidase,LOX）表达对人肺癌细胞95D乏氧转移的影响及其分子机制。方法应用针对人LOX基因的小于扰RNA（LOX siRNA）转染常氧（19％O2）95D细胞,24h后将细胞蚩乏氧（0．5％O2）培养箱孵育,乏氧24h后采用实时PCR检测细胞LOX mRNA和Snail mRNA表达,Western blot技术评价Src、磷酸化Src（P-Src Y418）和Snail蛋白表达,Transwell小空评价细胞侵袭能力．结果与常氧95D细胞比较,乏氧引起细胞LOX mRNA表达和细胞侵袭能力分别增加14倍和2．12倍。与对照siRNA组比较,LOX siRNA转染使乏氧细胞LOX mRNA表达下降70％～75％,侵袭能力下降约30％,P—Src Y418和Snail蛋白表达降低约40％（P〈0．05）,但不影响Src蛋白表达和Snail mRNA水平（P〉0．05）。结论LOX表达下调降低人肺癌细胞乏氧侵袭与减少Src活化和Snail蛋白表达有关,为LOX成为防治肺癌乏氧转移的潜在靶点提供了实验依据。     

铜在培养的大鼠心肌细胞上的抗氧化损伤作用

在培养的大鼠心肌细胞的培养基中加入0.42×10~-3 mol/L黄嘌呤及5.3×10~-9 mol/L黄嘌呤氧化酶可使心肌细胞产生氧化损伤,表现为APA、MDP、OS、Vmax减小,SDF增大;膜输入阻抗减小;细胞自由基含量增加;细胞的超微结构被破坏。向培养基中加0.0625ppm,Cu可阻止黄嘌呤及黄嘌呤氧化酶的氧化损伤作用。铜作为超氧化构歧化酶及细胞色素氧化酶的活性中心成份,可能通过提高这些酶的活性而起抗氧化及清除自由基作用。     

尼克酰胺腺嘌呤二核苷酸磷酸氧化酶在血管性认知障碍中的作用及其机制的研究进展

氧化应激(OS)是导致血管性认知障碍(VCl)的因素之一.尼克酰胺腺嘌呤二核苷酸磷酸(NADPH)氧化酶(NOX)产生的活性氧(ROS)是VCI重要的致病分子.VCI的危险因素如高血糖及缺血/再灌注等在上游增加NOX的活化;其他危险因素如高龄、高血压及卒中是NOX依赖ROS产生的下游损伤.VCI的成因包括与NOX相关的...     

经前舒颗粒对经前期综合征肝气郁证模型大鼠海马单胺氧化酶A、B表达的影响

目的：研究经前舒颗粒对经前期综合征（PMS）肝气郁证大鼠海马单胺氧化酶A/B（MAOA/B）表达水平的影响。方法：雌性未孕SD大鼠48只,随机分为3组：正常对照组、模型组、经前舒治疗组,束缚造模法复制PMS肝气郁证大鼠模型,旷场实验对模型进行评价,治疗组采用经前舒颗粒治疗,RT-PCR和Western blot方法分别检测各组大鼠海马MAOA/B的mRNA及蛋白的表达。结果：模型大鼠海马MAOA mRNA及蛋白表达显著升高,经前舒颗粒治疗后,MAOA mRNA和蛋白表达均显著降低,而MAOB mRNA和蛋白表达各组间没有显著性变化。结论：PMS肝气郁证大鼠海马MAOA表达出现异常,经前舒颗粒的作用机制可能是通过调节海马MAOA的表达而发挥作用。